i386/common/cons.c

	cons.c revision 199767f8919635c4928607450d9e0abb932109ce
/*-
 * Copyright (c) 1998 Robert Nordier
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms are freely
 * permitted provided that the above copyright notice and this
 * paragraph and the following disclaimer are duplicated in all
 * such forms.
 *
 * This software is provided "AS IS" and without any express or
 * implied warranties, including, without limitation, the implied
 * warranties of merchantability and fitness for a particular
 * purpose.
 */

#include <sys/cdefs.h>

#include <sys/param.h>

#include <machine/psl.h>

#include <btxv86.h>

#include "lib.h"
#include "rbx.h"
#include "util.h"
#include "cons.h"

#define SECOND      18  /* Circa that many ticks in a second. */

uint8_t ioctrl = IO_KEYBOARD;

void
putc(int c)
{

    v86.ctl = V86_FLAGS;
    v86.addr = 0x10;
    v86.eax = 0xe00 | (c & 0xff);
    v86.ebx = 0x7;
    v86int();
}

void
xputc(int c)
{

    if (ioctrl & IO_KEYBOARD)
        putc(c);
    if (ioctrl & IO_SERIAL)
        sio_putc(c);
}

void
putchar(int c)
{

    if (c == '\n')
        xputc('\r');
    xputc(c);
}

int
getc(int fn)
{

    /*
     * The extra comparison against zero is an attempt to work around
     * what appears to be a bug in QEMU and Bochs. Both emulators
     * sometimes report a key-press with scancode one and ascii zero
     * when no such key is pressed in reality. As far as I can tell,
     * this only happens shortly after a reboot.
     */
    v86.ctl = V86_FLAGS;
    v86.addr = 0x16;
    v86.eax = fn << 8;
    v86int();
    return fn == 0 ? v86.eax & 0xff : (!V86_ZR(v86.efl) && (v86.eax & 0xff));
}

int
xgetc(int fn)
{

    if (OPT_CHECK(RBX_NOINTR))
        return (0);
    for (;;) {
        if (ioctrl & IO_KEYBOARD && getc(1))
            return (fn ? 1 : getc(0));
        if (ioctrl & IO_SERIAL && sio_ischar())
            return (fn ? 1 : sio_getc());
        if (fn)
            return (0);
    }
    /* NOTREACHED */
}

int
keyhit(unsigned int secs)
{
    uint32_t t0, t1;

    if (OPT_CHECK(RBX_NOINTR))
        return (0);
    secs *= SECOND;
    t0 = 0;
    for (;;) {
        if (xgetc(1))
            return (1);
        if (secs > 0) {
            t1 = *(uint32_t *)PTOV(0x46c);
            if (!t0)
                t0 = t1;
            if (t1 < t0 || t1 >= t0 + secs)
                return (0);
        }
    }
    /* NOTREACHED */
}

void
getstr(char *cmdstr, size_t cmdstrsize)
{
    char *s;
    int c;

    s = cmdstr;
    for (;;) {
        switch (c = xgetc(0)) {
        case 0:
            break;
        case '\177':
        case '\b':
            if (s > cmdstr) {
                s--;
                printf("\b \b");
            }
            break;
        case '\n':
        case '\r':
            *s = 0;
            return;
        default:
            if (s - cmdstr < cmdstrsize - 1)
                *s++ = c;
            putchar(c);
            break;
        }
    }
}

int
getchar(void)
{
    return (xgetc(0));
}